Field of the Invention
The present invention relates to a composition for forming an interlayer insulating film, an interlayer insulating film, a method for forming an interlayer insulating film pattern, and a device.
Background Art
In recent years, as semiconductor devices have become more highly integrated and larger, there is a demand for thinner and smaller package substrates. In accordance with this, an interlayer insulating film of a package substrate including a surface protective layer, an interlayer insulating film, or a rewiring layer of the semiconductor device has been required to be formed with a material having more excellent electrical properties, heat resistance, and mechanical properties.
A polyimide resin (hereinafter, referred to as “PI”) and polybenzoxazole (hereinafter, referred to as “PBO”) are representative materials which may satisfy such required properties, and for example, the use of a photosensitive PI or a photosensitive PBO obtained by imparting photosensitivity to PI or PBO is considered.
When these photosensitive resins are used, there is an advantage that pattern forming steps are simplified and thus complicated manufacturing steps can be shortened. In addition, these photosensitive resins have improved heat resistance and insulation resistance as compared with a vinyl-based photosensitive resin of the related art which enables alkali developing by the introduction of a carboxy group, and are effectively used as the above-described interlayer insulating film (for example, refer to Japanese Unexamined Patent Application, Publication No. 2011-180472 and Japanese Unexamined Patent Application, Publication No. 2007-031511).
On the other hand, the photosensitive PI and the photosensitive PBO have problems that it is required to be baked at a high temperature (350° C. to 400° C.), and it has low exposure stability, large film reduction of a formed resin film, and low solvent solubility.
In contrast, an interlayer insulating film obtained by using a photosensitive acrylic resin having a good handleability and a high heat resistance has been proposed (refer to Japanese Unexamined Patent Application, Publication No. 2008-040183).